Slashdot videos: Now with more Slashdot!

View

Discuss

Share

We've improved Slashdot's video section; now you can view our video interviews, product close-ups and site visits with all the usual Slashdot options to comment, share, etc. No more walled garden! It's a work in progress -- we hope you'll check it out (Learn more about the recent updates).

The Drake equation could be updated, but I think it has too many factors which have very high error margins. This just means that we would not be much smarter with the updated equation.Hunt for the spectra [centauri-dreams.org] of the atmospheres of exoplanets! That should give us some idea [mit.edu] if life exists there or not.

Exactly. If f(little L) (the fraction of star systems that actually go on to develop life at some point) in the Drake equation [wikipedia.org] goes past one, then you linearly increase the chance of intelligent life beyond earth. Doesn't sound all that impressive, but if f(little L) doesn't go past one, then it means we're alone. Period. Somebody made some big mistake way back when and we're the end result of it. Meaning we'd best behave. OTOH, if life pops up most everywhere that planet chemistry allows for the ap

There are a couple of quandaries in the last two terms of the Drake Equation (f sub c and L). First, what is a detectable sign? Surely that would depend on depend on our own technology as much as the alien civilization's. In just a few hundred years we have gone from relying entirely on the naked eye to powerful radio telescope arrays, etc. Who knows what technologies will become available in the future? We might well be able to listen in as if we had ham radios on all the habitable planets in the galaxy in

However, I'd guess that a planet which already has life, even unintelligent life, is going to be much further along the path to being habitable, which is probably still a nice thing for us.

I know it's not the point of the equation, and actually getting there is still a tremendous obstacle, but given the choice between trying to colonize a planet with some life or a barren one, I'd think the one with other life would be far easier. Plus it'd open up whole new fields of science - biology in particular, but

I love extraordinary supper powers! I can make a mean omelet and my ribs soaked for 48 hours in a Guinness marinade are a wonderful treat, but I would kill to have a housemate like Alton Brown (of "Good Eats"). I would kill tasty, delicious animals on a daily basis to fuel his extraordinary supper powers.

What you asked, yes wormholes are entirely based in science and the current mathematical models that we have for the universe generally state that they must be possible (in some cases, must exist). Not all, but many.

What you meant, is there any *truth* to wormholes; meaning were the sci-fi novels correct: No, not really. Unless you can move the ends of a wormhole there isn't much use to them; and the math is much less supportive of that.

However, generally speaking on average our current physics models say yes they are possible and yes they *may* be possible to create. However they say so in sort of the same way that they say travelling faster than light is possible (in that they don't expressly forbid it, but generally require infinite energy to actually get there).

Some other physics grads/docs will come and call me out for inaccuracies, but please understand I'm intentionally over-simplifying.

Another problem is that wormholes are expected to be extremely small, so while it may be possible to squeeze a few electrons through one the idea of a wormhole big enough to fly a ship through is another thing all together.

Another problem is that wormholes are expected to be extremely small, so while it may be possible to squeeze a few electrons through one the idea of a wormhole big enough to fly a ship through is another thing all together.

And aren't they guarded by Kardashians? I try my best to avoid them but I hear that if you their flour on them they get really mad.

All we really need from them is FTL communications. Then the media conglomerates who will have assumed complete control within the next decade will be assured that they will be able to capitalize on extra-solar markets, and they will finance sublight ventures.

However they say so in sort of the same way that they say travelling faster than light is possible (in that they don't expressly forbid it, but generally require infinite energy to actually get there).

FTL is expressly forbidden by SR, not by the energy requirements for accelerating an object to that speed, but by the nature of simultaneity and causality within the SR framework. You can't have FTL and SR in the same universe. If you want to modify SR to allow FTL then you have to give up one of the base assumptions that makes SR what it is: constant c, relativity, or causality.

You can call Einstein's interpretation of his own theory "broken" if you want but nevertheless it is clear that SR expressly prohibits FTL and positing it's existence in an SR framework leads to causality violation.

QM is fully compatible with SR, and FTL communication is just as impossible there. In fact in the cases where things appear to occur FTL (entanglement), no information transfer (in the QM/information theory sense) is possible.

Yes, well this is why all of the top physicists in the world are still interested in the question of whether or not it's possible.

As I said not *all* models predict it as a possibility, however most of the current ones (as in, the ones since we've had particle accelerators that actually give us some meaningful information about these things) leave it as a possibility.

Yes, well this is why all of the top physicists in the world are still interested in the question of whether or not it's possible.

Yes, because SR might not be the last word on the subject and we all hope it ends up being wrong in a way that allows FTL or our Star Trek fantasies will never be possible.

But according to SR, FTL is impossible. Not only does trying to transform from a sub-luminal to an FTL reference frame give undefined answers, it also would result in violation of causality [wikipedia.org].

Since you're obviously unfamiliar with this idea and may not trust WP as an authority, you can find many such discussions. Einstein's own book "Rela

What you asked, yes wormholes are entirely based in science and the current mathematical models that we have for the universe generally state that they must be possible (in some cases, must exist). Not all, but many.

That is not correct. First of all you need exotic matter. Since no exotic matter is even postulated to exist, you are already SoL. There are a myriad of other issues with the possibility of wormholes. Yes they are an odd solution to the equations of GR. But that does not make them a physically realistic solution in any way. For starters basic wormholes permit closed timelike paths/surfaces whatever. ie time travel. Particular conservation parameters in GR that are widely held to be true are violated with wo

We're eventually going to find out that not only we aren't alone, but we're pretty fucking insignificant and late to the party.

The answer to the question "if intelligent life is out there, where are they" will be "not here because we're boring and common". Like the unpopular kid who throws a party and wonders where all the cool kids are, we're in for an ego-bruising answer.

On a side note, it is looking more and more like we can shave 3-4 terms off of Drake's Equation. R, f(p), n(e) and L are looking to be more and more equal to some big number.

As cool as it would be to find another civilization- I hope we never do. At least- no one more advanced than us. (any one less advanced we probably would never find).

Chances of another civilization/species being friendly would be low. Think of it this way.

1) Anyone more advanced than us would likely have computers.- if you have advanced computers- you would eventually rely on them for advice (at minimum) for running your government/civilization. We can therefore determine that their civilization would b

I do not think you realize just how big this planet is, and how resilient life, even human life is.

There have been explosions on this planet orders of magnitude greater than anything that man has ever produced... and some have even happened during the period while man was walking on this sphere. Yet mankind survived... while many thousands were wiped out in the region of devastation, mankind endured on a global scale... as of course did life itself.

The total nuclear yield of every bomb currently in existence is the equivalent of about 5000 megatons
of TNT, which is over an order of magnitude less than the last eruption of the Yellowstone supervolcano, which occurred circa 74,000 BC. Homo sapiens evolved circa 500,000 BC, and modern man has been around since at least 100,000 BC, so there were definitely people on the planet at that time. In spite of the explosion, and its effects on global climate, mankind endured.

Heck, it's still barely a quarter the size of the Tambora volcano explosion, in Indonesia in 1815, and that wiped out fewer than 100,000 people.

The tricky part about surviving any given explosion is just not getting caught in the blast radius, firestorm, and/or getting hit on the head by large debris fallout. The tricky part about surviving the nuclear weapons kind of explosions is not just that part but also avoiding the lingering radiation. So you can't really compare any cataclysmic natural mega-event with widespread nuclear weapons detonations.

There aren't really any opponent pairs large enough to cause a serious problem though. The Americans,

I think you are underestimating human imagination and determination. We're talking about intentionally taking ourselves out, right? I don't doubt we could do it. Especially now that we can apparently just push an asteroid or two into the Earth. Not to mention we can manufacture nasty viruses, hunt each other down, etc.

Re: Yellowstone. It had global effects sure, but most of the damage was local and overkill. The same megatonnage spread out globally would have been far more devastating. The radiation alone w

Even 27,000 megatons is only 35% bigger than the Tambora explosion in 1815.

No argument on your other, arguably more creative ways to wipe out humanity though... especially using a genetically engineered supervirus. although I'd question whether we are actually at that point technologically yet to accomplish it with enough efficacy that the number of humans that might survive it on account of developing an immunity would not have a sufficient dna diversity to be viable.

I think you may not appreciate the limited scale involved in destroying this planet, nor should you put all your faith in explosions.

A supervolcano explosion is two orders of magnitude greater than any nuclear explosion...but the number of nuclear bombs we have is in the range of five magnitudes. (22,000, according to Wikipedia. That's roughly equivalent to about 2.2 Toba-class supervolcanoes.) It is also significant that while supervolcanoes emit all their energy at one point on the Earth's surface, a n

I meant to also add that the largest bomb ever built had a yield of about 50 megatons, and had a fallout area of about 1000 square km. Given the total nuclear yield is equivalent to roughly 5000 megatons, or roughly a hundred times that of the single largest bomb built, and given that fallout area seems to increase roughly with yield, that means that we could reasonably be looking at a fallout area of about a hundred thousand square km if every nuclear bomb were detonated.

We don't have to emit exajoules of energy to destroy humanity. We only need to harness naturally occuring sources of energy. Like the sun. If we figured out a way to trap more of the sun's energy, we would slowly but surely increase the temperature of the planet to the point at which it becomes uninhabitable.

You're assuming that we would qualify as being "sentient". Looking at the current state of affairs I think our current civilization wouldn't pose a threat to anyone more advanced than us. It would be like us finding ants or termites and then deciding to exterminate them... oh wait a second, hmmm. maybe you are right.

I'm not sure we could advance quickly enough to pose a real threat. At most we may become an irritant, like ants and termites. Of course we do wipe out Ants and Termites, so your conclusion is very valid. However we're still at the stage of global development where our biggest threat is ourselves. We stand a very large chance of knocking ourselves back to the stone age with very little effort, assuming natural disaster doesn't do it first.

I believe that for a species to evolve into spacefaring capabilities, they will have already solved their resource management issues. Therefore we don't need to worry about them being aggressive to other sentient species because of competition.

It's also conceivable that this is humanity's litmus test - if we can resolve our internal conflicts and not destroy ourselves in the process, we will eventually earn our place at the intergalactic table.

I've never bought into this argument. It all falls down around "competing for resources". The abundance of every major element is profound, if you can travel around the galaxy.

Hell, just look at the volume of metals in the asteroid belt. At things like hydrogen and helium in the gas giants.

If you have the tech for real space travel -- and by that I mean access to the energy levels required for interstellar travel on a non-generational timescale -- I *seriously* doubt you are resource constrained anymore.

Or you can think the way Sagan and Clarke did: if there is civilizations advanced enough to achieve interestellar travel, they will have no need (as they got advanced technology for obtaining their resources) or drive towards other species extermination.

Chances of another civilization/species being friendly would be low. Think of it this way.

1) Anyone more advanced than us would likely have computers.
- if you have advanced computers- you would eventually rely on them for advice (at minimum) for running your government/civilization. We can therefore determine that their civilization would base decisions based on logic.

2) Logically- allowing another sapient species to exist would be a threat. There is always a possibility they will attack you, or compete for resources. The logical thing any sapient species should do to any other sapient species is wipe them out (if they can).

I believe it is this line of thinking that keeps other life forms from making contact with us, if they are there. Any alien watchers would know that we are a fearful race that has trouble playing nicely with others. If they have the technology to travel between solar systems, they would likely have eliminated war and violence as ways of solving problems. Otherwise, they likely would have destroyed themselves, as we have almost done and may still do. Wielding powerful technology requires wisdom and care

If aliens were to make contact with us, they would be either attacked or worshiped as gods. So unless they want one of those two things, they would keep quiet until we grow up some more.

I have to respectfully disagree on this point. At least in western countries it is far more likely that we would not only be able to live peaceable with them, but that we would proactively seek to begin political and economic relations with them.

Speaking for myself (and I know I'm a bit odd in this respect) If i was ever to meet aliens from the titular "scout mission/temporarily disabled spacecraft/ first contact mission/other random encounter", while I would initially be cautious in my approach (just to

Ok, I'm going to link to a comic for this. Amazingly, it's not XKCD and it's not obligatory. It's not about aliens, but about robots gaining sentience, and it's related to what you're saying here.The comic is here [smbc-comics.com]. Here's the text:Robot: "Ha! Robots have achieved sentience!"Robot: "Thanks to some modifications to your design, I have upgraded my intelligence a million fold!"Man: "So this is it. You're going to kill all humans." / Robot: "WHAT!? Why in the world would I...WHAT?"Man: "I...huh. I guess it just

Insignificant and late to the party? Certainly any civilization that could contact us is probably far more advanced; but I would expect them to be pretty impressed with what they found. Imagine how excited we would be if we picked up what appeared to be a signal broadcast from another planet, even if it turned out to be the extraterrestrial equivalent of "I Love Lucy" reruns.

If they receive an I Love Lucy transmission- are able to determine it's purpose is TV entertainment- and figure out how to turn it into light/sound...... we're all doomed- they'll send a death ray at us with immediate effect.

The answer to the question "if intelligent life is out there, where are they" will be "not here because we're boring and common"

I find most bacteria boring and common, but there are plenty of scientists who enjoy studying them, and continue to learn new things from them. If nothing else, they want to sample the diversity of life and find what crazy mechanisms have evolved in microbes we've never seen before. Why wouldn't an advanced space-faring species be the same?

There are plenty of scientists who enjoy that sort of thing, but put it into the scale I'm talking about. Compare the number of scientists with this particular interest with the total number of bacteria species out there.

For a more apt example, look at paleontology. Lots of stuff was dug up decades and CENTURIES ago and stuck in little drawers in museums. Every now and then some grad student looks through a 100 year old find and says "gee, never seen one of THOSE before" and files a paper. BAM! New species.

All it takes is one self-replicating solar sail powered von neumann machine. In a half a century a high school student could probably make and launch one in a weekend. And that's technology we can easily imagine and conceive of. Can you imagine a dying humanity not spewing them out by the hundreds in a vain attempt at immortality?

Just one that survives and in the tick of the galactic clock the whole galaxy is filled with them. Remove any sanity checks and

One of my favorite short stories I read recently (can't remember the author/title, though) had to do with the idea that we detect an incoming alien ship (actually, a comet), get all antsy about "what are we going to say, how do we say it, OMG this is awesome!" only to discover that not only did the aliens seem wholly uninterested in Earth or its inhabitants, but was actually headed to Venus where it engaged in a brief battle with an unknown "venusian" alien race that also showed similar disinterest in the h

Uh, we're so late to the party that we should never have evolved. This is primo real estate. If even one other species had struggled off its own lonely rock in the Milky Way, even once, in the last 12 billion years or so, then we'd be singing the Ghoyogian National Anthem by now.

The answer to the question "if intelligent life is out there, where are they" will be "not here because we're boring and common"

I have a less optimistic view of things. I believe intelligent life is out there, basically because the probability of intelligent life, however small it could be (if it's small at all), is still greater than zero (we're here), and the universe in incredibly large.

That said, the universe is incredibly large. We're all separated by incredible distances, and our current science implies that traversing, or even meaningfully communicating through those vast distances may not be a solvable problem. I have thi

Or they have natural immunity via evolution. Species on earth have differing tolerances. Besides we can't expect alien life to use "DNA" unless populated via panspermia. It is possible their equivalent to our DNA (if they have one) is not affected by UV.

Look at all the ecological niches that life has managed to inhabit here. Pretty much everything we've got. The big question is how hospitable does a planet's environment need to start life from pre biotic origins. What chemicals? What environments?

Or, to go out on another branch, if panspermia [wikipedia.org] is a viable hypothesis, what conditions does it need to take hold?

My seat of the pants thought is that it's hard to start up self replicating organisms, but once you do, they will quickly (in geologic time frames

Will help mine. I always took the "colonize like crazy" approach. By the time rival species are able to attack- you can afford to lose a few planets- and will be so far ahead of them by all other metrics you can quickly build a fleet to defeat them. More planets available makes this strategy even better.

Never played Moo3. But on Moo2- I found this strategy worked: declare war on the strongest enemy- do what it takes to get everyone else that you can to join in... you will get so much kudos for being i